Method of forming tampons



March 28, 1939. J. WEBB 2,152,230 7 METHOD OF FORMING 'IAMI ONS Filed June 29/ 1936 I 2 Sheets-Sheet l INVENTOR.

ATTORNEYS INVENTOR.

2' Sheets-Sheet 2 ATTORNEYS J. L. WEBB METHOD OF FORMING TAMPONS Filed June 29, 1956 March 28, 1939.

Patented Mar. 28, 1939 PATENT OFFICE.

METHOD OF FORMING TAmoNs John L. Webb, Los Angeles, Calif., assignor to Holly-Pax, Inc., Los Angeles, Calif., a corporation of California Application June'29, 1936, Serial No. 87,866

4 Claims.

This invention relates to the manufacture of bodies of fibrous material such as cotton for use in absorbing moisture and fluids in body cavities and to methods and machines for forming such bodies. It has todo more specifically with the manufacture of vaginal tampons which consist of cylindrical or prismatic bodiesv of cotton or similar absorbentfibrous material compressed laterally substantially to the limit of compressibility of the material. Such tampons are relatively rigid, compact and self-retaining, retaining their compressed dimensions so long as they remain dry but when wetted they quickly expand and become soft and absorbent.

An object of the invention is to produce a compressed tampon in shape approximating a cylinder or a prism in Which-the fibrous material is compressed substantially radially inwardly from all sides whereby the tampon when moistened is free to expand radially substantially uniformly in all directions from the axis of the tampon. Such a tampon expands more uniformly and fully than does one made by compressing a mass of fibrous material in one or two directions only.

Another object is to increase the speed and reduce the cost of making laterally compressed tampons.

Another object is to provide an automatic machine capable of operating continuously to com- 30 press tampons. I

Various other objects and features of the invention will become apparent from the following detailed description which refers to the drawings.

In the drawings:

35 Fig. l is an elevation view of a complete machine in accordance with the invention with part of the casing broken away to show the interior mechanism, the view being taken in the direction I in Fig. 2; i

Fig. 2 is a plan view of the compressing machine with the upper frame plate removed to show the compressing jaws;

Fig. 3 is a partial view similar to Fig. 2 with the mechanism in a diflerent phase of its opera- 45 tion;

Fig. 4 is a vertical sectional view of the main portion of the machine, the section being taken along the line IV-IV of Fig. 2;

Fig. 5 is a detail sectional view through one of the links actuating the compressing levers, the section being taken along the line V-V in Fig. 2;

Fig. 6 is a sectional view through one of the compressing levers, the section being taken along the line VI-VI of Fig. 2;

Fig. '7 is a detail sectional viewshowing the (c1. na -55) tampon supporting gate, the section being taken along the line VIL-VII of Fig. 2;

Fig. 8 is a side view of a cylindrical tampon adapted to be compressed in accordance with the invention;

Fig. 9 is a side View of the tampon after being compressed in my machine; and

Fig. 10 is a detail elevation view of certainelements of the machine which appear in plan in Fig. 2.

The machineto be described operates on loose, approximately cylindrical tampons such as shown in Fig. 8 and functions to compress such tampons laterally by applying pressure at a plurality of circumferentially spaced areasto a smaller diameter, as shown in Fig. 9. The tampons shown in Figs. 8 and 9 comprise a body of fibrous ma- 7 terial I having a pull string 2 imbedded therein.

The loose tampons shown in Fig. 8 may be formed in any desired manner and the pull string 2 may be anchored in any desired manner, such methods not constituting a part of the present invention. However, the loose tampons shown in Fig. 8 may be conveniently formed by winding a strip of cotton into a loose roll of desired dimensions. The machine shown in Fig. l is adapted to receive large, loose, cylindrical tampons I, compress theminto compact form and discharge them. Thus, as shown in Fig. l, the loose tampons may be continuously delivered by a belt conveyor 3 to the hopper or chute 4 of a compressing machine 5, from which after compression they drop onto a second conveyor belt 6 which carries them away to be packed. The unit 5 is provided with a pulley 1 which may be driven through a beltB from the pulley 9 of an electric motor I0. Both the motor Ill and the compressing unit 5 may be supported upon a suitable bench or table II.

Referring now to Fig. 4, the compressing machine 5 comprises a supporting frame consisting of a base plate l2 which may be anchored to the supporting table or bench H in any convenient manner, a second plate [3 positioned above the base plate I2, a third plate l4 positioned above the plate 13, and an upper plate l5 positioned above the third plate. The plate I3 is supported from the plate l2 by pillars l6 and plates l4 and I5 are connected together and supported from the plate l3 by pillars l1 and I8. The pillars [B may be threaded at their lower ends into the plate l2 and have reduced threaded portions at the upper end which pass through apertures provided therefor in the plate l3 and are locked to the plate l3 by nuts 19. The pillars Il may likewise have reduced end portions threaded in the plate I 3 and reduced upper end sections which pass through apertures provided therefor in the plate l4 and screw into the lower ends of the pillars l8, the latter having reduced upper end sections which pass through the plate l5 and are provided with retaining nuts 20. A cylindrical dust cover 2| fits about the plates I2, I3 and I5 and extends over the top of the plate l5 and is shaped to define the chute 4. However, cover 2| does not form any part of the frame of the machine.

Centrally disposed within the machine is a shaft 23 which is rotatably mounted by a ball bearing 24 in the plate 12 and by bushings 25 and 26 in the plates I3 and I4, respectively. The ball bearing 24 supports the weight of the shaft and the parts connected thereto in addition to absorbing lateral thrust. The bushings 25 and 26 merely absorb the lateral thrust of the shaft. Shaft 23 is hollow to provide a central passage 2! through which compressed tampons are dropped onto the conveyor belt 6. The shaft 23 has keyed thereto a large gear 28 which meshes with a pinion 29 keyed to the shaft 30 which supports the drive pulley l. The shaft 30 is rotatablysupported in bushings 31 and 32 in the plates 12 and I3, respectively. It is apparent, therefore, that shaft 23 is rotated through pinion 29 and gear 28 in response to rotation of the drive pulley 7. The shaft 23 also has keyed thereto between the plates l3 and M a small gear 33 which meshes with five gears 34 positioned in planetary fashion concentrically about the shaft 23, each gear 34 being pinned to a shaft 35 rotatably supported in bushings 36 and 31 in the plates l3 and I4, respectively. These shafts extend through and beyond the bushings 31 above the plate l4 and terminate in crank arms 38 having crank pins 39 which actuate the tampon compressing members.

Thus referring to Fig. 2, each crank pin 39 is coupled through a pitman 40 to the end of the long arm 4| of a lever 42 fulcrumed on a stationary pin 43 and having a short arm 44, the inner end of which constitutes one of the tampon compressing jaws. As the shafts 35 rotate, the levers 42 are oscillated back and forth between the position shown in Fig. 2 and Fig. 3, respectively. In Fig. 3 the jaws are in open position in which there is ample space between them to receive the uncompressed tampon and in Fig. 2 the jaws are shown in fully closed position in which they have compressed the tampon substantially to the limit of compressibility of the material of which it is constructed.

Referring now to Fig. 5, which showsin detail the construction of the pitmans 40, each pitman consists of an elongated member 45 having a transverse journal 46 in one end to receive the associated driving pin 39 and having a longitudinal recess in the other end, this recess receiving a rod 41 which is pivotally connected at its outer end by a pin 48 to the bifurcated end of the long arm 41 of the associated lever 42. The rod 41 is threaded on its inner end into a bushing 49 which is fitted for longitudinal sliding movement within the member 45 and bears against a helical compression spring 50 which is retained by a bushing 5| threaded into the outer end of the member 45. The spring 56 is relatively stiff and normally maintains the inner end of the rod 41' against the end of the recess in member 45. The function of this spring is to permit the pitman to yield slightly in response to excessive resistance to movement of the associated lever 42' and prevent stalling of the driving motor or breakage of the machine. Resiliently yieldable pitman rods are quite essential in a machine of the type described for the reason that the tampons are compressed substantially to the limit of compressibility of the material and, if an over-sized tampon were introduced or should some solid object be introduced between the jaws, the jaws would be prevented from assuming their closed position as shown in Fig. 2 and some part of the machine would then be broken if the driving motor did not stall. The tension of the spring 50 may be adjusted by disconnecting the rod 41 from the associated lever; and screwing the rod in or out of the bushing 49. To prevent rotation of the bushing 49-, the latter is provided with a longitudinal slot into which a pin 56 projects from the member 45.

The pins. 43 upon which the levers 42 are fulcrumed may be screwed into threaded apertures provided therefor in the plate I 4, as shown in Fig. 6. The upper ends of these pins 43 may extend into apertures provided therefor in the upper plate- I5 so that they are supported at both I ends.

Referring for the. moment to Fig. 1, the tam- .pons- I. may be supplied continuously to the compressing machine. 5 by the belt conveyer 3 and the tampons may: beso spaced along the belt relative to; the speed of the latter as to drop a tampon into the hopper 4 periodically as the compressing jaws assume their open position, as shown in 3, thetampons falling directly from the chute 4 intothe space between the open jaws. It is necessary, however, to support the tampons at the level of the jaws until the jaws close sufficiently to engage the tampons. To this end, a tamponsupporting gate is provided immediately below the jaws, this gate consisting of a flat bar 51: which is slidable longitudinally in a recess or groove; provided therefor in the upper face of the plate M. The upper endof the bushing 26 is also cut. away on one side to accommodate the gate the inner end of the gate being rounded as shown: inv Fig. 2to fit againstthe bushing. The gate member 51 extends radially with respect to the axis of the shaft 231 out beyond the plate I4 and is provided on its outer end with an actuating roller-58: which extends down below the plate M into the path. of an actuating spring lever 59 which, as shown in Fig. 10, is supported at one glnld to the periphery of: the plate M as by screws Referring now to" Fig. 2; the spring lever 59 normally rests loosely against-the roller 58 when the gate member 5'l is in innermost position, the latter being retained in thisposition by a tension spring:6lanchored tothe plate I 4. The spring lever 5.9? extendsbeyondr the gate member 57 into a position to be periodically intercepted by a roller 62 mounted upon one of the gear 34 asshowrr in Fig. 7. Phe roller 62 is so positioned on the gear 34 as to intercept the spring lever 59' and move; it outward; thereby moving the gate member 5'!- outward as the compressing jaws open so that before the jaws reach their fully open position, as shownin Fig. 3, the inner end of the gate member 51 is retracted away from the passage 21 in the shaft 23, permitting the compressed tampon to drop away from the compressing. jaws. As-the roller 62 continues its travel it:passes beyond theend of the spring lever 59, permitting; the gate member 5'! to be snapped back by the spring SI and: close the upper end of' the passage 2'! by the time, the compressing jaws have fully opened and a new tampon has been delivered thereto.

It will be observed from inspection of Figs. 2 and 3 that the tips of the short arms 44 of the levers 42, which constitute the compressing jaws, have compressing motions which may be resolved into rotary and radial components with respect to the central axis of the machine. However, the rotary components of the motions of these jaws produce no compressing effect on a tampon position therebetween for the reason that the latter is freely supported by the jaws and rotates in response to the rotary components of movements of the jaws. Therefore, the only force that is effective to compress the tampon is that resulting from the radial components of the movements of the jaws. As a result, the compression in the tampon is the same as would result if a plurality of jaws were forced radially inwardly toward the common axis without having any rotary component whatsoever. This is an advantageous feature of the machine since any rolling or twisting compressive force on the tampons tends to wrap or twist the fibers so that they do not reexpand, when wetted, as freely as they do when the compression is substantially radial.

In order to provide a larger opening for receiving the loose tampons, the inner sides of the short arms 44 of the levers, when the latter are in open position as shown in Fig. 3, may be made somewhat concave as indicated at 10 to provide a slightly larger opening. However, as soon as the levers have progressed an appreciable distance in their compressing movement, the concave faces 10 no longer touch the tampons, the tips only of the short arms 44 bearing against the tampons.

It has been found that, although in a machine as described pressure is applied to a tampon at five distinct circumferentially spaced areas, the resulting tampon has a surface that is relatively smooth and is really more cylindrical than prismatic in shape, as would be expected. This probably results from the fact that in their compressing movement the jaws rotate slightly over the surface of the tampon, applying the pressure at slightly different points thereon during the different stages of compression. Obviously, it is not essential to employ five compressing jaws as shown. The number may be increased or may be reduced but the larger the number of jaws employed the more nearly cylindrical the finished tampon will be.

Although the invention has been described in detail with reference to a particular construction, many modifications and departures from the particular machine shown may be made while still employing the essential principles and features of the invention. Theinvention is therefore to be limited only as set forth in the appended claims.

I claim:

1. The method of producing a tampon of absorbent fibrous material, which tampon is relatively dense, rigid and self-retaining while dry but expands into a much larger, soft and porous body when wetted, said method consisting in the steps of first forming a loose, large, approximately cylindrical tampon uncompressed in a longitudinal direction from said material in dry, loose condition and then laterally compressing the tampon while dry by simultaneously applying equal pressure to at least three circumferentially spaced areas of its lateral surface, each of said spaced areas extending longitudinally substantially the full length of the tampon, said pressure being in a transverse direction only.

2. The method of producing a tampon of absorbent fibrous material, which tampon is relatively dense, rigid and self-retaining while dry but expands into a much larger, soft and porous body when wetted, said method consisting in the steps of first forming a loose, large, approximately cylindrical tampon uncompressed in a longitudinal direction from said material in dry, loose condition and then laterally compressing the tampon while dry by simultaneously applying equal pressure to at least three circumferentially spaced areas of its lateral surface, each of said spaced areas extending longitudinally substantially the full length of the tampon, and the pressure applied being sufiicient to compress said material substantially to the limit of compressibility of the material, said pressure being in a transverse direction only.

3. The method of producing a tampon of absorbent, fibrous material, which tampon is relatively dense, rigid and self-retaining while ,dry but expands into a much larger, and soft and porous body when wetted, said method consisting in the steps of first forming a loose radially large approximately cylindrical tampon uncompressed in a longitudinal direction from said material in dry, loose condition, and then laterally compressing the tampon while dry by simultaneously applying equal pressure to at least three circumferentially spaced areas of its lateral surface, each of said spaced areas extending longitudinally substantially the full length of the tampon, and progressively applying said pressure to areas of smaller and smaller circumferential extent as the lateral dimensions of the tampon are reduced by compression, said pressure being in a transverse direction only.

4. The method of producing a tampon of absorbent fibrous material, which tampon is relatively dense, rigid and self-retaining while dry but expands radially only into a much larger, soft and porous body when wetted, the method consisting in the steps of first forming a loose, radially large, approximately cylindrical tampon from said material in dry, loose condition, and then laterally compressing the tampon while dry by simultaneously applying equal pressure to at least three circumferentially spaced areas of its 

